<template>
  <div>
    <!-- 面包屑导航区域 -->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>分类参数</el-breadcrumb-item>
    </el-breadcrumb>
    <!-- 卡片视图区域 -->
    <el-card>
      <!-- 头部警告区域 -->
      <el-alert
        title="注意：只允许为第三级别分类设置相关参数"
        type="warning"
        :closable="false"
        show-icon>
      </el-alert>
      <!-- 选择商品分类区域 -->
      <el-row class="cat_opt">
        <el-col>
          <span>选择商品分类：</span>
          <!-- 选择商品分类的级联选择框 -->
          <el-cascader
            expand-trigger="hover"
            v-model="selectedCateKeys"
            :options="catelist"
            :props="cateProps"
            @change="handleChange">
          </el-cascader>
        </el-col>
      </el-row>
      <!-- tab 页签区域 -->
      <el-tabs v-model="activeName" @tab-click="handleTabClick">
        <!-- 添加动态参数的面板 -->
        <el-tab-pane label="动态参数" name="many">
          <!-- 添加参数的按钮 -->
          <el-button type="primary" size="mini" :disabled="isBtnDisabled" @click="addDialogVisible = true">添加参数</el-button>
          <!-- 动态参数表格 -->
          <el-table
            :data="manyTableData"
            border
            stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染 tag 标签 -->
                <el-tag v-for="(item, i) in scope.row.attr_vals" :key="i" closable @close="handleClose(i, scope.row)">
                  {{item}}
                </el-tag>
                <!-- 输入文本框 -->
                <el-input
                  class="input-new-tag"
                  v-if="scope.row.inputVisible"
                  v-model="scope.row.inputValue"
                  ref="saveTagInput"
                  size="small"
                  @keyup.enter.native="handleInputConfirm(scope.row)"
                  @blur="handleInputConfirm(scope.row)">
                </el-input>
                <!-- 添加的按钮 -->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index" label="序号"></el-table-column>
            <el-table-column label="参数名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit" size="mini" @click="showEditDialog(scope.row.attr_id)">修改</el-button>
                <el-button type="danger" icon="el-icon-delete" size="mini" @click="removeParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>

        <!-- 添加静态属性的面板 -->
        <el-tab-pane label="静态属性" name="only">
          <!-- 添加属性的按钮 -->
          <el-button type="primary" size="mini" :disabled="isBtnDisabled" @click="addDialogVisible = true">添加属性</el-button>
          <!-- 静态属性表格 -->
          <el-table
            :data="onlyTableData"
            border
            stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染 tag 标签 -->
                <el-tag v-for="(item, i) in scope.row.attr_vals" :key="i" closable @close="handleClose(i, scope.row)">
                  {{item}}
                </el-tag>
                <!-- 输入文本框 -->
                <el-input
                  class="input-new-tag"
                  v-if="scope.row.inputVisible"
                  v-model="scope.row.inputValue"
                  ref="saveTagInput"
                  size="small"
                  @keyup.enter.native="handleInputConfirm(scope.row)"
                  @blur="handleInputConfirm(scope.row)">
                </el-input>
                <!-- 添加的按钮 -->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index" label="序号"></el-table-column>
            <el-table-column label="属性名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit" size="mini" @click="showEditDialog(scope.row.attr_id)">修改</el-button>
                <el-button type="danger" icon="el-icon-delete" size="mini" @click="removeParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
      </el-tabs>
    </el-card>

    <!-- 添加参数的对话框 -->
    <el-dialog
      :title="'添加' + titleText"
      :visible.sync="addDialogVisible"
      width="50%"
      @close="addDialogClosed">
      <el-form
        :model="addForm"
        :rules="addFormRules"
        ref="addFormRef"
        label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="addForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="addDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="addParams">确 定</el-button>
      </span>
    </el-dialog>

    <!-- 修改参数的对话框 -->
    <el-dialog
      :title="'修改' + titleText"
      :visible.sync="editDialogVisible"
      width="50%"
      @close="editDialogClosed">
      <el-form
        :model="editForm"
        :rules="editFormRules"
        ref="editFormRef"
        label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="editDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="editParams">确 定</el-button>
      </span>
    </el-dialog>
  </div>
</template>

<script>
export default {
  data() {
    return {
      // 保存商品分类列表数据
      catelist: [],
      // 级联选择框的配置对象
      cateProps: {
        value: 'cat_id',
        label: 'cat_name',
        children: 'children'
      },
      // 级联选择框双向绑定到的数组
      selectedCateKeys: [],
      // 被激活的页签的名称
      activeName: 'many',
      // 保存动态参数的数据
      manyTableData: [],
      // 保存静态属性的数据
      onlyTableData: [],
      // 控制添加参数对话框的显示与隐藏
      addDialogVisible: false,
      // 添加参数的表单数据对象
      addForm: {
        attr_name: ''
      },
      // 添加参数的表单验证规则对象
      addFormRules: {
        attr_name: [
          { required: true, message: '请输入参数名称', trigger: 'blur' }
        ]
      },
      // 控制修改对话框的显示与隐藏
      editDialogVisible: false,
      // 修改的表单数据对象
      editForm: {},
      // 修改表单的验证规则对象
      editFormRules: {
        attr_name: [
          { required: true, message: '请输入参数名称', trigger: 'blur' }
        ]
      }
    }
  },
  created() {
    this.getCateList();
  },
  methods: {
    // 获取所有的商品分类列表
    async getCateList() {
      const { data: res } = await this.$http.get('categories');
      if (res.meta.status !== 200) {
        return this.$message.error('获取商品分类失败！');
      } else {
        this.catelist = res.data;
        // console.log(this.catelist)
      }
    },
    // 级联选择器选中项变化，会触发这个函数
    handleChange() {
      // 调用参数的列表数据
      this.getParamsDate();
    },
    // tab 页签点击事件的处理函数
    handleTabClick() {
      // console.log(this.activeName)
      // 调用参数的列表数据
      this.getParamsDate();
    },
    // 获取参数的列表数据
    async getParamsDate() {
      // 证明选中的不是三级分类
      if (this.selectedCateKeys.length !== 3) {
        // 清空级联选择器双向绑定到的数组
        this.selectedCateKeys = [];
        // 清空动态参数的数据
        this.manyTableData = [];
        // 清空静态属性的数据
        this.onlyTableData = [];
      } else {
        // 根据所选分类的 Id，和当前所处的面板，获取对应参数
        const { data: res } = await this.$http.get(`categories/${this.cateId}/attributes`, {
          params: { sel: this.activeName }
        });
        if (res.meta.status !== 200) {
          return this.$message.error('获取参数列表失败！');
        } else {
          // console.log(res.data);
          // 通过循环把字符串转为数组
          res.data.forEach(item => {
            // 如果 vals 值不为空则返回值，如果为空则返回空数组
            item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
            // 控制文本框的显示与隐藏
            item.inputVisible = false;
            // 文本框中输入的值
            item.inputValue = ''
          })
          // console.log(res.data)
          if (this.activeName === 'many') {
            this.manyTableData = res.data;
          } else {
            this.onlyTableData = res.data;
          }
        }
      }
    },
    // 监听添加参数对话框的关闭事件
    addDialogClosed() {
      this.$refs.addFormRef.resetFields();
    },
    // 添加参数---点击按钮，添加参数
    addParams() {
      this.$refs.addFormRef.validate(async valid => {
        if (!valid) return;
        const { data: res } = await this.$http.post(`categories/${this.cateId}/attributes`, {
          attr_name: this.addForm.attr_name,
          attr_sel: this.activeName
        });
        if (res.meta.status !== 201) {
          return this.$message.error('添加参数失败！');
        } else {
          this.$message.success('添加参数成功！');
          this.addDialogVisible = false;
          this.getParamsDate();
        }
      })
    },
    // 点击修改按钮，展示修改的对话框
    async showEditDialog(attrId) {
      // 查询当前参数的信息
      const { data: res } = await this.$http.get(`categories/${this.cateId}/attributes/${attrId}`, {
        params: { attr_sel: this.activeName }
      });
      if (res.meta.status !== 200) {
        return this.$message.error('获取参数信息失败！');
      } else {
        this.editForm = res.data;
      }
      // 显示修改对话框
      this.editDialogVisible = true
    },
    // 监听修改对话框的关闭事件
    editDialogClosed() {
      this.$refs.editFormRef.resetFields();
    },
    // 点击按钮修改参数信息
    editParams() {
      this.$refs.editFormRef.validate(async valid => {
        if (!valid) return;
        const { data: res } = await this.$http.put(`categories/${this.cateId}/attributes/${this.editForm.attr_id}`, {
          attr_name: this.editForm.attr_name,
          attr_sel: this.activeName
        });
        if (res.meta.status !== 200) {
          return this.$message.error('修改参数失败！');
        } else {
          this.$message.success('修改参数成功！');
          // 调用参数的列表数据
          this.getParamsDate();
          // 关闭修改参数对话框
          this.editDialogVisible = false;
        }
      })
    },
    // 根据 ID 删除对应的参数项
    async removeParams(attrId) {
      const confirmResult = await this.$confirm('此操作将永久删除该参数, 是否继续?', '提示', {
        confirmButtonText: '确定',
        cancelButtonText: '取消',
        type: 'warning'
      }).catch(err => err)
      if (confirmResult !== 'confirm') {
        return this.$message.info('与取消删除！');
      } else {
        // 删除的业务逻辑
        const { data: res } = await this.$http.delete(`categories/${this.cateId}/attributes/${attrId}`);
        if (res.meta.status !== 200) {
          return this.$message.error('删除参数失败！');
        } else {
          this.$message.success('删除参数成功！');
          // 调用参数的列表数据
          this.getParamsDate();
        }
      }
    },
    // 文本框失去焦点，或摁下了 Enter 键都会触发
    async handleInputConfirm(row) {
      if (row.inputValue.trim().length === 0) {
        row.inputValue = '';
        row.inputVisible = false;
      } else {
        row.attr_vals.push(row.inputValue.trim());
        row.inputValue = '';
        row.inputVisible = false;
        // 需要发起请求保存这次操作
        this.saveAttrVals(row);
      }
    },
    // 将对 attr_vals 的操作，保存到数据库
    async saveAttrVals(row) {
      // 需要发起请求保存这次操作
      const { data: res } = await this.$http.put(`categories/${this.cateId}/attributes/${row.attr_id}`, {
        attr_name: row.attr_name,
        attr_sel: row.attr_sel,
        attr_vals: row.attr_vals.join(' ')
      });
      if (res.meta.status !== 200) {
        return this.$message.error('修改参数项失败！');
      } else {
        this.$message.success('修改参数项成功！');
      }
    },
    // 点击按钮显示文本输入框
    showInput(row) {
      row.inputVisible = true;
      // 让文本框自动获得焦点
      // $nextTick 方法的作用，就是当页面上元素被重新渲染之后，才会指定回调函数中的代码
      this.$nextTick(_ => {
        this.$refs.saveTagInput.$refs.input.focus();
      });
    },
    // 点击删除对应的参数可选项
    handleClose(i, row) {
      row.attr_vals.splice(i, 1);
      // 发起删除参数项的请求
      this.saveAttrVals(row);
    }
  },
  // 计算属性
  computed: {
    // 如果按钮需要被禁用，则返回 true，否则返回 false
    isBtnDisabled() {
      if (this.selectedCateKeys.length !== 3) {
        return true
      } else {
        return false
      }
    },
    // 获取当前选中的三级分类的 Id
    cateId() {
      if (this.selectedCateKeys.length === 3) {
        return this.selectedCateKeys[2];
      } else {
        return null;
      }
    },
    // 动态计算参数对话框的标题的文本
    titleText() {
      if (this.activeName === 'many') {
        return '动态参数'
      } else {
        return '静态属性'
      }
    }
  }
}
</script>

<style lang="less" scoped>
.cat_opt {
  margin: 15px 0;
}

.el-tag {
  margin: 0 10px;
}

.input-new-tag {
  width: 120px;
}
</style>
